3 * Copyright (c) 2012 Paul B Mahol
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/intreadwrite.h"
27 static int avr_probe(AVProbeData
*p
)
29 if (AV_RL32(p
->buf
) != MKTAG('2', 'B', 'I', 'T'))
32 if (!AV_RB16(p
->buf
+12) || AV_RB16(p
->buf
+12) > 256) // channels
33 return AVPROBE_SCORE_EXTENSION
/2;
34 if (AV_RB16(p
->buf
+14) > 256) // bps
35 return AVPROBE_SCORE_EXTENSION
/2;
37 return AVPROBE_SCORE_EXTENSION
;
40 static int avr_read_header(AVFormatContext
*s
)
42 uint16_t chan
, sign
, bps
;
45 st
= avformat_new_stream(s
, NULL
);
47 return AVERROR(ENOMEM
);
49 st
->codec
->codec_type
= AVMEDIA_TYPE_AUDIO
;
51 avio_skip(s
->pb
, 4); // magic
52 avio_skip(s
->pb
, 8); // sample_name
54 chan
= avio_rb16(s
->pb
);
56 st
->codec
->channels
= 1;
57 } else if (chan
== 0xFFFFu
) {
58 st
->codec
->channels
= 2;
60 avpriv_request_sample(s
, "chan %d", chan
);
61 return AVERROR_PATCHWELCOME
;
64 st
->codec
->bits_per_coded_sample
= bps
= avio_rb16(s
->pb
);
66 sign
= avio_rb16(s
->pb
);
68 avio_skip(s
->pb
, 2); // loop
69 avio_skip(s
->pb
, 2); // midi
70 avio_skip(s
->pb
, 1); // replay speed
72 st
->codec
->sample_rate
= avio_rb24(s
->pb
);
73 avio_skip(s
->pb
, 4 * 3);
74 avio_skip(s
->pb
, 2 * 3);
78 st
->codec
->codec_id
= ff_get_pcm_codec_id(bps
, 0, 1, sign
);
79 if (st
->codec
->codec_id
== AV_CODEC_ID_NONE
) {
80 avpriv_request_sample(s
, "Bps %d and sign %d", bps
, sign
);
81 return AVERROR_PATCHWELCOME
;
84 st
->codec
->block_align
= bps
* st
->codec
->channels
/ 8;
86 avpriv_set_pts_info(st
, 64, 1, st
->codec
->sample_rate
);
90 AVInputFormat ff_avr_demuxer
= {
92 .long_name
= NULL_IF_CONFIG_SMALL("AVR (Audio Visual Research)"),
93 .read_probe
= avr_probe
,
94 .read_header
= avr_read_header
,
95 .read_packet
= ff_pcm_read_packet
,
96 .read_seek
= ff_pcm_read_seek
,
98 .flags
= AVFMT_GENERIC_INDEX
,